[core] Collapse duplicate to_remove_ read in Scheduler::call fast path

Read to_remove_ once at the top of the cleanup block instead of loading
it twice (once via cleanup_() -> to_remove_empty_(), once again for the
MAX_LOGICALLY_DELETED_ITEMS check). GCC cannot CSE across the memw
barriers that std::atomic<uint32_t>::load emits on Xtensa, so both the
fast-path zero check and the max check were generating independent
memw + l32i sequences:

    memw; l32i a8, [to_remove_]; beqz ...   ; to_remove_empty_()
    memw; l32i a8, [to_remove_]; bltui 5    ; to_remove_count_()

Reading the counter once into a register and branching on the result
collapses the common zero-case to a single memw + l32i + beqz. The
non-zero path pays one extra read after cleanup_slow_path_ (which may
have decremented the counter), but that path already takes lock_ so the
extra load is negligible.

Scheduler::call stays at 344 B (unchanged); no flash layout shift, so
adjacent code (feed_wdt_slow_ etc.) stays in the same cache lines and
the measurement can't be confounded by MMIO timing drift.

An earlier version of this change also marked Scheduler::millis_64()
ESPHOME_ALWAYS_INLINE to drop its out-of-line $isra$0 clone; that
grew Scheduler::call by 56 B, shifted feed_wdt_slow_ in flash, and
measurably regressed the wdt bucket on a busier winefridge.yaml
config, so the inlining is dropped. This change keeps only the memw
collapse.

.pre-commit-config.yaml

@@ -11,7 +11,7 @@ ci:
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
     # Ruff version.
-    rev: v0.15.11
+    rev: v0.15.12
     hooks:
       # Run the linter.
       - id: ruff

esphome/components/sendspin/__init__.py

@@ -193,7 +193,7 @@ async def to_code(config: ConfigType) -> None:
         )
 
     # sendspin-cpp library
-    esp32.add_idf_component(name="sendspin/sendspin-cpp", ref="0.3.0")
+    esp32.add_idf_component(name="sendspin/sendspin-cpp", ref="0.3.1")
 
     cg.add_define("USE_SENDSPIN", True)  # for MDNS
 

esphome/core/scheduler.cpp

@@ -601,14 +601,24 @@ uint32_t HOT Scheduler::call(uint32_t now) {
   }
 #endif /* ESPHOME_DEBUG_SCHEDULER */
 
-  // Cleanup removed items before processing
-  // First try to clean items from the top of the heap (fast path)
-  this->cleanup_();
+  // Cleanup removed items before processing. Read the counter once so the
+  // common zero-case is a single atomic load + branch; the old code called
+  // cleanup_() (which loads to_remove_) and then to_remove_count_() again for
+  // the MAX check, producing a redundant memw+load pair on the fast path.
+  // GCC cannot CSE across the memw barriers that std::atomic<uint32_t>::load
+  // emits on Xtensa, so the duplicate load was unavoidable without manual
+  // restructuring.
+  if (this->to_remove_count_() != 0) {
+    // First try to clean items from the top of the heap (fast path).
+    this->cleanup_slow_path_();
 
-  // If we still have too many cancelled items, do a full cleanup
-  // This only happens if cancelled items are stuck in the middle/bottom of the heap
-  if (this->to_remove_count_() >= MAX_LOGICALLY_DELETED_ITEMS) {
-    this->full_cleanup_removed_items_();
+    // If we still have too many cancelled items, do a full cleanup.
+    // This only happens if cancelled items are stuck in the middle/bottom
+    // of the heap. Re-read to_remove_ because cleanup_slow_path_ may have
+    // decremented it.
+    if (this->to_remove_count_() >= MAX_LOGICALLY_DELETED_ITEMS) {
+      this->full_cleanup_removed_items_();
+    }
   }
   // IMPORTANT: This loop uses index-based access (items_[0]), NOT iterators.
   // This is intentional — fired intervals are pushed back into items_ via

esphome/idf_component.yml

@@ -92,6 +92,6 @@ dependencies:
   esp32async/asynctcp:
     version: 3.4.91
   sendspin/sendspin-cpp:
-    version: 0.3.0
+    version: 0.3.1
   lvgl/lvgl:
     version: 9.5.0

requirements.txt

@@ -6,7 +6,7 @@ colorama==0.4.6
 icmplib==3.0.4
 tornado==6.5.5
 tzlocal==5.3.1    # from time
-tzdata>=2026.1  # from time
+tzdata>=2026.2  # from time
 pyserial==3.5
 platformio==6.1.19
 esptool==5.2.0

requirements_test.txt

@@ -1,6 +1,6 @@
 pylint==4.0.5
 flake8==7.3.0  # also change in .pre-commit-config.yaml when updating
-ruff==0.15.11  # also change in .pre-commit-config.yaml when updating
+ruff==0.15.12  # also change in .pre-commit-config.yaml when updating
 pyupgrade==3.21.2  # also change in .pre-commit-config.yaml when updating
 pre-commit